Rodents, in particular mice, are extensively used by research projects of several SDRC investigators. An animal core is thus an important component of the SDRC that has been providing expertise and training in the successful completion of animal experiments in a cost effective and highly predictable manner. There is considerable emphasis on skin cancer in the SDRC. There is evident by the fact that 1) five nationally funded projects of this faculty either conduct murine skin tumorigenicity experiments or utilize cutaneous tumors developed on murine skin for biochemical morphological , and molecular biological studies, 2) one of the pilot and feasibility proposed in this renewal application will conduct murine skin tumorigenesis experiments, 3) in the NIH funded training program in Investigative and Molecular Dermatology there are four training tracks, one of which emphasizes skin carcinogenesis. Out of the two current trainees supported by this training grant, one utilizes murine skin tumors and the other conducts animal experiments. The developing emphasis is to utilize chemically mutagenized mice which have clinical phenotypes for dermatitis, susceptibility to UV, cancer and blistering diseases. The additional areas of research in SDRC are a) structural biology and genetics of the skin, and b) immunodermatology. Several investigators conducting research in these areas do animal experimentation. This core has enabled SDRC investigators to conduct animal experimentation more efficiently. The core has four specific functions. The first function is to provide SDRC faculty with a) tissue, in particular tumors, from cutaneous tumor-bearing and age- and sex- matched normal mice, and b) homogenate, RNA, DNA, and single cell suspensions, from defined tumors of variously treated mice. The second function is to provide expertise in planning, procurement, and handling of specialized animals for experiments to be conducted by SDRC faculty. Within this objective, the core serves as a resource center in a) providing technical expertise and advise in producing transgenic and knockout mice, and b) conducting experiments on nude mice, e.g. tumor development and their histological verification. The third, which is a newly added function, relates to screening, maintaining and breeding chemically mutagenized mice with clinical phenotypes of skin disease of interest to SDRC investigators. These mice should prove valuable in dissecting complex multi-gene phenotypes. The fourth function of the core is to provide SDRC faculty with biostatistical expertise. For all, experiments involving animal work being conducted and planned for the near future, expertise in murine skin carcinogenesis, biochemistry, genetics, biostatisticians, histopathology and veterinary husbandry and care is needed. Together Core Director, Co-Directors and Consultants represent a team capable of providing expertise in all aspects of animal experimentation.